System Information
Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: Intel(R) HD Graphics 620 Intel 4.5.0 - Build 23.20.16.4973
Blender Version
Broken: version: 2.80 (sub 75), branch: master, commit date: 2019-07-29 14:47, hash: rBf6cb5f54494e
Worked: (optional)
Short description of error
'Save As...' accidentally replaces any blend fill without warning.
Exact steps for others to reproduce the error
Goto 'File | Save As...' and select any blend file and click 'Save As Blender File' - No Warning!
[Based on the default startup or an attached .blend file (as simple as possible)]
Use any file.